Press for propeller blade sections



F. A. GRUETJEN PRESS FOR PROPELLER BLADE SECTIONS 4 sheets-sheet 1 Filed Aug; 14, 1944 Frederick A. Gnieg'jzz ATTORNEY Aug. 31, 1948. v F. A. GRUETJEN PRESS FOR PROPELLER BLADE SECTIONS 4 Sheets-Sheet 2 Filed Aug. 14, 1944 Frederick A. eruezjm AT Tommy Y F. A. GRUETJEN PRESS FOR vPROPELLER BLADE SECTIONS Aug. 31, 1948.

4 Sheets-Sheet 3 Filed Aug. 14, 194-4 Frederick A. Gzzzezjezz ATTORNEY F. A. GRUETJEN PRESS FOR PROPELLER BLADE SECTIONS Aug. 31, 1948.

4 Sheets-Sheet 4 Filed Aug. 14, 1944 FIG-7.

Frederick A. Graze z 'en INVENTOR.

AT T0 RNEY.

Patented Aug. 31, 1948 1 2.,l44l179: I

PRES -non rnorntmmemnnisnouons Frederick A: .Gi netiemaMilvvaukee;'.,wisr,.assignork HA1 Smith:: C,orponation;,Milwaukee; Wisx, 3e corporatiomofiNew York, Application An us-e14, 194d: $eria{No.--549466 s Glaima (Cl. Hag-48);

This invention relates to a press-for pnopeller blade sections aunt-the like, wherein-a tubular biankiis fiattened to bladeshape; I

Tne pnin-cipal objeet of therinventionris to provtde'iwpress-in whichthe blank is expan'de-di-invone d-iametrica'l direc'tion while it' is being contra-cted'i int az. diametrical direction at substantially rlght angles tb the firsti Another object of the invention is to provide: such? at press.- wherein both" the expansion and contraction are obtained from avsingle relative motion of the press platens.

Anntherrobjecta is tm provide: a; simple and effieientz expandingcmandrel:operatemby theiplatena movementofia: presssto'zexpan'dra blankxinithefli esi. Qthen' objects and s advantages: willhe set; forth: hmeinaftemn. connectiom With; the: description tof anembodiment: of-ztherinventionaillustrated" in ther aocoltmpany, ing::draw'ings':v

' Inithevdrawingsz 'Ffigure-i-lsis a siderelevationicf the'press Eig; is-i a; rightehandf; end elevation of.-: the" Eigz. 6t a: central; longitudinal; vertical; sect-ioni takenaon'lline lie-noting; with thexdiegop'en;

and andnel expanded; and

E1 this! a top; plan: view-of thepress; with; the

111111612 platen and die operating cams removed.

The press. comprises. a comnavctt die-unit l that cambesecuned tov-thesplatens v2t and- 3 tot ant: suit-f fine 1mm constituteslthe important pait-offthe; inventi'ontandcomprises a. baseplate 5 adaptezcit'o.v be; .snnpo1tted. upon the. lowen' fixedlplaten 2. of; they press, and an upper: punch member fi having a flatitopadapted to besecuredto theupper platen 3i-ofitlie'press.

rne" dies '1" andjfiextendilongitudinally. oi" the; umtlvandi'are adapted;to move laterally, toward and'away from one another. The dies Tjand'B rest'uponiwear plates B'fs-etin a recess in base plate ifand' a; Temem'ber lb'securedf'to the base plate" has its head 'Iti ing,.,in a similarly. shapedf'slotfin the. dies-and?interlocked'therewith to holdthe dies in' alignment? flfid inneiffaces ofithe idiesTand-B are. recessed for-receiving andi forming the? blank H which in the iilustiatiommay' constitn-te ar tu-Bul'ar tip se Fig; 74s asimilargsectionsshowing the :diBSiClOSGd".

2 tion forraipropelleribladehaving le-ading and-traile ing fedge fihst I zzextendingi-in a'aslig'htispiral ii'ntliewblame to correspond-twitnthmtwist :of 'thaabladbt The outersside facesaofi the dies: Ti'fllfld'i agar slanting ast an angie from-:the perpendicularean haveiwear plates: ['3 securedztheneto. Thepunchr memben fi: has'downwardly-z depending side-imeme hers I 4 fw hich have their innerr faces slanting :in at complementary manner to the slanting sides-ion; the dies and. locateda to: efiectzmovement: of the dies towardloneanotherbyawedgingmctiomwhen thespun'ch is forced downwardly in: engagement-g withthewearrplatesd"3:.

'Iihe dies .--1 randsafaredieldwoutwardly againstithe'; slantin'gtsurfaees ofithepunch by-me'anszof;avpairf of: springs? I51: on each side;. The springsz area. mounted OHiStUd' -bOItS 16 secured in the -diememberszatiopposite. ends of the punch sidemembers; l4 and-:passingithrough:openingsdn-the respective. upstanding-post's: ITonrthe basexplate; Eachiboltft I 6 -;is'. adapted to reciprocate through the:- opening inathe respective stationary 'post. l 'l andmarriesiaat coil? spring." l 515 disposed: between: the;v head of the bolt:and the.post-biasing thearespectivesdietmem ber outwardly.

Wear plates l klaresecuredfto the outensidesof the punch side members Ilrandiengagetheiinnem su rfaces of th estationary: posts .t o" guideithemunch in its downward. movement andrpreventa defiec t'ion'ofthe side members .I 4.

the flattening of a tinsectioni Unit. is Dre ferred'ito expan'dfthe blank-:inone direction as its iSi flattened: in' the.- other. For;- this. purpose the presentxinvention provides an expanding mandrel: 19: comprising; v central longitudinallytapered? wedge member ZD-eonnected by alongzitudinal Tesiot interlock toz-an upper edge 2il= andetojaalowerr edge 22, the edges 2| and 22 being:shapedtoren-t gag-e1 tha -blank; through-out its length at: the -root ofithe-fins |2, andthe entire'mandrel being shaped to -correspondfwithithe internal shape of thewbiank upon completion-of"the fia'ttening operation.

The central-wedge member -20iz is forced longi ltndinally betweenedees 2| and Z-Z- as the-punch 6 is" lowered; This is accomplished by securing an, upright guide '23 to the-base 5 at the rearend -of the dies 1 and 8, and spaced-"therefrom. The uide iii-has a'slanting cam surface 24 at the'-'bot-- tomof a groove 25in its=-face toward"the' dies.

Plates- ZB Secnred-to the upright 23 partially close the groove 2='5- to form it 5 into a" T-s-lot; A pivot" block 2 T rides up 5 and down" in'; the groo've--2 5- and" has a link 23 pivoted-theretoafidtoabracket29 secured to; the underside of theflatatop 'ofpunch.

the end of wedge member 20. Movement of punch 6 up and down effects sliding of block 21 along cam surface 24 in stationary grooves 25 and thereby effects outward and inward movement of wedge member 20 in mandrel l9. Shims 3| may be placed between bracket 29 and punch 6 and serve to provide for adjustment of the movement and position of wedge'member 20 relative to the dies 1 and 8.

Movement of the blank II and of the edges 2| and 22 longitudinally during forming is prevented by the tie bar 32 extending across the top of the two posts I! to the rear of the dies 1 and 8. A similar tie bar 33 extends across the top of the two posts I1 at the front end of the dies 1 and 8. The tie bar 32 engages blank and also of the dies 1 and 8 and serves to hold them in alignment. Flanges 34 on the rear ends of mandrel edges 2| and 22 also engage the dies to hold the edges against forward movement when wedge member 20 is forced forwardly therebetween. A cover plate ,35 is secured to the posts IT at the rear and prevents rearward movement of mandrel edges 2| and 22 while allowing the edges to move apart to effect the spreading of the blank in a vertical direction. The shank of member 20 rides in a guideway 36 in plate 35 which supports the mandrel horizontally.

The apparatus is loaded and unloaded at the front end where a trap door arrangement secures the blank in place during forming. The trap door 3'! is hinged along its bottom edge to the base plate to pivot between an open horizontal position for loading the dies and a closed vertical position-for operation-of the dies. A drop latch 33 is pivoted to the door 31 near the free edge of the latter and. has a shoulder 39 for engaging an abutment 40 on the base 5.

A handle M on. latch 38 provides for manually raising the latter to disengage the shoulder '39 and abutment 40, when it is desired to drop the door 31 to horizontal position. The door 31 has a gate 62 through which the end of wedge-member 20 freely extends.

The blank H is supported centrally of the dies when first inserted in the press, by a pair of spring pressed lever arms 43 pivoted on brackets 44 on the wear plates 9 and extending upwardly into engagement with the lower edge, of the blank. The forward support arm 43 has a roller 45 at its upper end for engaging the blank and allowing freedom of movement of the lever arm along the blank when the latter is expanded downwardly. A stop 46 is provided on the lower end of each lever 53 to limit the upward position of the lever arm when there is no blank H in the press.

In operation the punch 6 is raised to its upper position with wedge member 20 withdrawn to the rear to contract mandrel l9 and with the dies 1 and 8 biased outwardly by springs l5. The latch 38 is disengaged and trap door 3'! dropped to horizontal position. The blank II is then inserted over the mandrel l9 and the trap door 3! closed and secured by dropping latch 38 against abutment 40. Then the punch 6 is lowered. As the side members [4 engage and wedge dies 1 and 8 inwardly toward one another the link 28 pushes block 21 down the inclined surface 24 in groove 25 and thereby forces the wedge member 20 forwardly between mandrel edges 2| and 22, spreading the latter apart vertically. I

Thus, as the dies 1 and 8 press the sides of blank I I inwardly, the edges 2| and 22 of manthe end of the 4 drel l9 spread the blank vertically until it fills the recesses in the dies. The spreading pressure of the mandrel on the blank H should exceed the collapsing pressure of the dies thereon so that the forming results primarily from a stretching of the blank as distinguished from a collapsing of the same. The design of the machine ma even provide for a sequence of operationwherein the dies 1 and 8 do not close upon the blank until the mandrel l9 has fully or nearly completely expanded the blank vertically. In this way there is less friction between the blank and dies and the latter serve to coin the final shape of the blank.

After forming of the blank the punch 6 is lifted, thereby retracting the member 20 and loosening the mandrel l9, and at the same time allowing the dies to be separated by the biasing action of springs l5. The latch 38 is then released and door 31 dropped. The formed blank can then be removed.

'In the forming of a propeller blade tip, it is preferable to employ two separate flattening steps in addition to a pre-spreading step. In carrying these flattening steps out, two separate flattening presses are employed, one only par tially flattening the blank, and the other completing the flattening to final propeller size and shape.

The invention may have various embodiments within the scope of the accompanying claims.

I claim:

1. In a press, a pair of platens relatively movable toward and away from each other, a mandrel supported by one of said platens for holding a blank therebetween, said mandrel having at least two longitudinally tapered members disposed for enlargement in one direction by relative longitudinal movement therebetween, means operated by the closing of the platens toward one another to effect relative longitudinal movement between the tapered mandrel parts' tending to expand the mandrel, said means comprising a cam surface guide member secured to the platen supporting the mandrel, and a slide block engaging said guide and linked to one of said mandrel parts and to the other platen.

2. In a press, a pair of platens relatively movable toward and away from each other, a mandrel therebetween and having a central longitudinal wedge member disposed between blank engaging members to separate the same and spread the blank when the wedge member is moved inwardly of'the mandrel in a direction at an angle to the direction of relative movement of said platens, and means to operate said mandrel wedge member in response to relative movement of said platens, said means comprising a cam member disposed at an angle between said platens and held by one of said platens, and a cam follower therefor linked to said central wedge member and to the other platen.

3. In a press, a pair of platens relatively movable toward and away from each other, a mandrel therebetween and having a central longitudinal wedge member disposed between blank engaging members to separate the same and spread the blank when the wedge member is moved inwardly of the mandrel in a direction at an angle to the direction of .relative movement of said platens, means to operate said mandrel wedge member in response to relative movement of said platens, a pair of dies on either side of said mandrel, and means to move said dies toward one-another to compress the blank therebetween in response to relative movement of said platens toward one another, said mandrel operating means comnising a cam member disposed at one end of the dies at an angle to the direction of relative movement of the platens and held by one of said platens, and a cam follower therefor linked to said central wedge member and to the other platen.

4. In a press, a pair of platens relatively movable toward and away from each other, a mandrel disposed therebetween with its axis at substantially right angles to the direction of relative movement between said platens and having a plurality of longitudinal members at least one of which is tapered to effect enlargement of the mandrel by wedging action upon movement of the tapered member, means to operate said mandrel \vedge member in response to relative movement of said platens, a pair of dies on either side of said mandrel, means to move said dies toward one another in a direction substantially at right angles to the axis of the mandrel and to the direction of relative movement between said platens to compress the blank therebetween in coordinated response to relative movement of said platens toward one another, and means to secure said blank upon said mandrel and in alignment with the dies, said first named means comprising cam members disposed between said platens and secured and held by one thereof, and a cam follower carried by the other of said platens and linked to said wedge member to operate the latter.

5. In a press, a pair of platens relatively movable toward and away from each other, a mandrel disposed with its axis at right angles to the direction of relative movement between the platens for holding a blank therebetween, said mandrel having a plurality of longitudinal members at least one of which is tapered to efiect enlargement of the mandrel by wedging action upon longitudinal movement of the tapered member, a cam track carried by one of said platens having a forward cam guide surface and a reverse cam guide surface, a cam follower carried by the other of said platens and disposed between said cam guide surfaces to respond to the forward cam guide surface as one platen moves relatively toward the other and to the reverse cam guide surface as one platen moves relatively away from the other, and means connecting said cam follower to said tapered mandrel member to effect forward and reverse movements of the member correlated to the corresponding movements of the follower.

6. In a press, a pair of platens relatively movable toward and away from each other, a mandrel carried by one of said platens and disposed with its axis at right angles to the direction of relative movement between the platens for holding a blank therebetween, said mandrel having a plurality of longitudinal members at least one of which is tapered to effect enlargement of the mandrel by wedging action upon longitudinal movement of the tapered member, a cam track carried by one of said platens having a forward cam guide surface and a reverse cam guide surface, a cam follower carried by the other of said platens and disposed between said cam guide surfaces to respond to the forward cam guide surface as one platen moves relatively toward the other and to the reverse cam guide surface as one platen moves relatively away from the other, means connecting said cam follower to said tapered mandrel member to effect forward and reverse movements of the members correlated to the corresponding movements of the follower, a pair of laterally movable dies carried by the platen which supports the mandrel, said dies being adapted to move toward each other to form a blank on said mandrel, and cam means carried by the other platen disposed to engage said dies and to effect inward movement of the same in correlation to the operative movements of said mandrel.

FREDERICK A. GRUE'I'JEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

